Examine source code of happy hacker

{
  "name": "Hacker Yellow Dark Experiment",
  "manifest_version": 2,
  "version": "1.0",
  "browser_specific_settings": {
    "gecko": {
      "id": "{d9f44bf7-a45e-4450-979c-91cf07434c3d}",
      "strict_min_version": "69.0"
    }
  },
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/happy.gif",
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right bottom",
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat",
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(255, 255, 255, 0)",
      "toolbar_text": "rgb(0, 247, 0)",
      "frame": "rgb(17, 17, 17)",
      "tab_background_text": "rgb(0, 247, 0)",
      "toolbar_field": "rgba(0, 0, 0, 0)",
      "toolbar_field_text": "rgb(0, 247, 0)",
      "tab_line": "rgb(0, 247, 0)",
      "popup": "rgb(17, 17, 17)",
      "popup_text": "rgb(0, 247, 0)",
      "popup_border": "rgb(0, 247, 0)",
      "sidebar_border": "rgb(0, 247, 0)",
      "sidebar_highlight_text": "rgb(255, 255, 255)",
      "sidebar_highlight": "rgb(17, 17, 17)",
      "sidebar_text": "rgb(255, 255, 255)",
      "sidebar": "rgb(17, 17, 17)",
      "ntp_background": "rgb(17, 17, 17)",
      "ntp_text": "rgb(0, 247, 0)",
      "tab_loading": "rgb(0, 247, 0)",
      "toolbar_top_separator": "rgb(0, 0, 0, 0)",
      "toolbar_field_border_focus": "rgb(17,17,17)"
    }
  }
}